/**
 * ref: https://github.com/PanJiaChen/vue-element-admin/blob/master/src/layout/components/TagsView/index.vue
 *
 * + 支持标签组 tagsGroup
 */

const state = {
  visitedViews: [],
  cachedViews: []
}

const mutations = {
  ADD_VISITED_VIEW(state, view) {
    if (state.visitedViews.some(v => v.path === view.path)) return

    let isReturn = false
    if (state.visitedViews.some(v => view.meta.tagsGroup && v.tagsGroup === view.meta.tagsGroup)) {
      isReturn = true

      // 查找到对应标签组名相同的标签，清除缓存并修改对应的信息
      for (const visitedView of state.visitedViews) {
        if (view.meta.tagsGroup && visitedView.tagsGroup === view.meta.tagsGroup) {
          for (const i of state.cachedViews) {
            if (i === visitedView.name) {
              const index = state.cachedViews.indexOf(i)
              state.cachedViews.splice(index, 1)
              break
            }
          }
          visitedView.name = view.name
          visitedView.path = view.path
          visitedView.fullPath = view.fullPath
          visitedView.title = view.meta.tagsTitle || view.meta.title || 'no-name'
          break
        }
      }
    }
    if (isReturn) return

    state.visitedViews.push(
      Object.assign({}, view, {
        title: view.meta.tagsTitle || view.meta.title || 'no-name',
        tagsGroup: view.meta.tagsGroup || 'no-tagsGroup'
      })
    )
  },
  ADD_CACHED_VIEW(state, view) {
    if (state.cachedViews.includes(view.name)) return
    if (!view.meta.noCache) {
      state.cachedViews.push(view.name)
    }
  },

  UPDATE_VISITED_VIEW: (state, view) => {
    for (let v of state.visitedViews) {
      if (v.path === view.path) {
        v = Object.assign(v, view)
        break
      }
    }
  },

  DEL_VISITED_VIEW: (state, view) => {
    for (const [i, v] of state.visitedViews.entries()) {
      if (v.path === view.path) {
        state.visitedViews.splice(i, 1)
        break
      }
    }
  },
  DEL_CACHED_VIEW: (state, view) => {
    for (const i of state.cachedViews) {
      if (i === view.name) {
        const index = state.cachedViews.indexOf(i)
        state.cachedViews.splice(index, 1)
        break
      }
    }
  },
  DEL_OTHERS_VISITED_VIEWS(state, view) {
    state.visitedViews = state.visitedViews.filter(v => v.meta.affix || v.path === view.path)
    // for (const [i, v] of state.visitedViews.entries()) {
    //   if (v.path === view.path) {
    //     state.visitedViews = state.visitedViews.slice(i, i + 1)
    //     break
    //   }
    // }
  },
  DEL_OTHERS_CACHED_VIEWS: (state, view) => {
    for (const i of state.cachedViews) {
      if (i === view.name) {
        const index = state.cachedViews.indexOf(i)
        state.cachedViews = state.cachedViews.slice(index, index + 1)
        break
      }
    }
  },
  DEL_ALL_VISITED_VIEWS: state => {
    state.visitedViews = state.visitedViews.filter(v => v.meta.affix)
  },
  DEL_ALL_CACHED_VIEWS: state => {
    state.cachedViews = []
  }
}

const actions = {
  addView({ dispatch }, view) {
    dispatch('addVisitedView', view)
    dispatch('addCachedView', view)
  },
  addVisitedView({ commit }, view) {
    commit('ADD_VISITED_VIEW', view)
  },
  addCachedView({ commit }, view) {
    commit('ADD_CACHED_VIEW', view)
  },

  updateVisitedView({ commit }, view) {
    commit('UPDATE_VISITED_VIEW', view)
  },

  delView({ dispatch, state }, view) {
    return new Promise(resolve => {
      dispatch('delVisitedView', view)
      dispatch('delCachedView', view)
      resolve({
        visitedViews: [ ...state.visitedViews ],
        cachedViews: [ ...state.cachedViews ]
      })
    })
  },
  delVisitedView({ commit, state }, view) {
    return new Promise(resolve => {
      commit('DEL_VISITED_VIEW', view)
      resolve([ ...state.visitedViews ])
    })
  },
  delCachedView({ commit, state }, view) {
    return new Promise(resolve => {
      commit('DEL_CACHED_VIEW', view)
      resolve([ ...state.cachedViews ])
    })
  },

  delOthersViews({ dispatch, state }, view) {
    return new Promise(resolve => {
      dispatch('delOthersVisitedViews', view)
      dispatch('delOthersCachedViews', view)
      resolve({
        visitedViews: [ ...state.visitedViews ],
        cachedViews: [ ...state.cachedViews ]
      })
    })
  },
  delOthersVisitedViews({ commit, state }, view) {
    return new Promise(resolve => {
      commit('DEL_OTHERS_VISITED_VIEWS', view)
      resolve([ ...state.visitedViews ])
    })
  },
  delOthersCachedViews({ commit, state }, view) {
    return new Promise(resolve => {
      commit('DEL_OTHERS_CACHED_VIEWS', view)
      resolve([ ...state.cachedViews ])
    })
  },

  delAllViews({ dispatch, state }, view) {
    return new Promise(resolve => {
      dispatch('delAllVisitedViews', view)
      dispatch('delAllCachedViews', view)
      resolve({
        visitedViews: [ ...state.visitedViews ],
        cachedViews: [ ...state.cachedViews ]
      })
    })
  },
  delAllVisitedViews({ commit, state }) {
    return new Promise(resolve => {
      commit('DEL_ALL_VISITED_VIEWS')
      resolve([ ...state.visitedViews ])
    })
  },
  delAllCachedViews({ commit, state }) {
    return new Promise(resolve => {
      commit('DEL_ALL_CACHED_VIEWS')
      resolve([ ...state.cachedViews ])
    })
  }
}

export default {
  namespaced: true,
  state,
  mutations,
  actions
}
